Since her early twenties, makeup artist Emma Johnson has needed frequent courses of antibiotics to help treat recurrent and painful urinary tract infections.
However, even though the antibiotics her doctor prescribed were effective in fighting the infection, Emma thinks it had an unwanted side effect: weight gain.
Emma, 38, believes that the antibiotics she took for seven days at a time, ten times a year for about 18 years, were responsible for her weight swelling from 9 to 12, from size 10 in her early twenties to size. 16 today.
She says she usually eats three meals a day without snacks, but when she was on a dose of antibiotics, she found herself constantly starving, with a gnawing hunger she found hard to resist.
Emma, 38, believes that the antibiotics she took for seven days at a time, ten times a year for about 18 years, were responsible for her weight bulge from nine to twelve.
The antibiotics always worked quickly and gave me relief but I’ve noticed side effects of desperate hunger. I couldn’t stop eating,” says Emma, a mother of two from Dartford, Kent.
There is evidence to support this. A 2017 animal study by the Liggins Institute at the University of Auckland in New Zealand found that increased antibiotic use increases the risk of obesity — in addition to affecting the body’s immune system or causing frequent diarrhea.
Meanwhile, young children who regularly took antibiotics were more likely to become obese than those who took fewer medications, according to a 2018 study in the journal Gut.
The seven-year study, which looked at 333,000 children who were given any antibiotics in the first two years of life, concluded that early exposure to antibiotics altered their gut microbiome — the microorganisms that live in our digestive system, eliminating harmful bacteria. It produces important nutrients – and increases the likelihood of obesity.
Recent research has suggested that gut bacteria may play a role in appetite (by affecting signals from hormones that regulate appetite).
Emma, who first developed a UTI at age 20 before suffering from multiple infections each year, says she noticed a distinct change in her appetite when she was on the medication.
“My stomach was always ringing and I was constantly raiding cupboards for snacks and wanted extra servings at mealtimes,” she says. “It was completely spent.”
The antibiotics always worked quickly and gave me relief but I’ve noticed side effects of desperate hunger. I couldn’t stop eating,” says Emma, a mother of two from Dartford, Kent
But as soon as she stopped the medication, her hunger subsided after a day or two. Unsurprisingly, she was also gaining weight.
“I started a size 10 before taking the antibiotics, but noticed my clothes got a little tighter after my period,” she says.
“I lost weight afterwards with my appetite decreased but sometimes the UTIs were close – two or three weeks apart – which meant I was regularly taking another course of antibiotics, and gaining weight.”
The problem occurred even when taking different types of medication, and she “always ended up feeling very hungry”.
“The hunger was so intense that it was impossible to ignore,” she says. “I would even eat at night, stand in front of the fridge at three in the morning, and eat whatever I could find.”
When she talked about the weight gain to her doctor, he didn’t think it was caused by the antibiotics.
However, a possible link between weight gain and antibiotics first emerged in the early days of drug use. For example, in 1951, researchers noted that when premature babies in Italy were given a daily dose of the antibiotic chlortetracycline, after ten days they were 8 percent heavier than untreated babies.
In 2014, leading US microbiologist Dr. Martin Placer and his team looked at data from the Avon Longitudinal Study of Parents and Children, an ongoing British project that began in the early 1990s. They found that children who were given antibiotics during the first six months of life became fatter than those who did not take them.
These findings led Dr. Placer and other researchers to believe that the rapid increase in obesity worldwide may be driven in part by exposure to antibiotics. What is the possible link? Gut bacteria or microbiome.
The problem with antibiotics is that although they eliminate the bacteria responsible for disease, they also eliminate the bacteria that keep you healthy. Without a balance, the microbiome can be thrown into disarray.
This can affect levels of the “hunger hormone” – which is secreted in the stomach lining and sends messages to the brain telling you to eat. High levels of ghrelin also lead to fat storage.
“We have bacteria everywhere in our bodies, and they work to our advantage by digesting foods,” says Colin Garner, Professor of Pharmacology and Toxicology and CEO of Antibiotic Research UK. But it can also be harmful, for example when it causes an infection.
Treatment with antibiotics leads to a loss of diversity in the gut bacteria, which leads to the production of signals in the intestine that lead to increased production of the hormone ghrelin in the stomach.
Ghrelin stimulates the appetite and the feeling of hunger, which causes the individual to eat more. It has been known for many years that when antibiotics are fed to farm animals such as pigs, the pigs gain weight. The same thing is likely to happen in humans.
Babies are generally born with a healthy balance of good and bad gut bacteria, and they also receive an extra supply of good bacteria through breastfeeding.
Professor Garner says this helps protect them from obesity, diabetes and mental health problems later in life.
Clearing the good bacteria with antibiotics can cause the bad bacteria to dominate – so the good bacteria can’t re-establish themselves.
Because children’s bodies develop rapidly, they are more susceptible to changes in the microbiome. This can have adverse effects later in life, such as obesity, diabetes, mental health problems, cardiovascular disease and irritable bowel syndrome (IBS), Professor Garner adds.
Taking a course of antibiotics even once can cause the release of hormones, especially ghrelin. In fact, researchers have found that transplanting bacteria from overweight humans into animals makes the animals obese.
“Disrupting the balance of bacteria through the killing effects of antibiotics will affect people in unpredictable ways,” says Professor Garner.
For some people, the problem is not hunger, but the opposite effect, whereby the drugs make the patient feel so sick that they can lose weight.
Prof Garner says we should limit our use of these drugs: “Most healthy people can fight infection without the need for antibiotics.”
But he agrees that for some people with recurrent infections, such as Emma, there is no other option. He suggests that those taking antibiotics focus on eating a healthy diet with plenty of fruit and vegetables, to help feed the “good” microorganisms.
Peter Worwell, consultant gastroenterologist and professor of medicine at the University of Manchester, suggests that taking probiotics can also help after taking antibiotics.
“In gastroenterology, we see a lot of problems after using antibiotics, and in IBS we see large numbers of people having their problems as a result of antibiotic use,” he says.
He adds that it is not narrow-spectrum antibiotics, such as penicillin, that are the problem because these “only kill two organisms”; It’s the broad spectrum “that kills everything in sight”.
“Because the antibiotics killed everything, they give the organisms that aren’t the best in you a chance to thrive.”
He argues that it makes sense to use probiotics to re-establish a gut that has been destabilized by antibiotics. This is supported by studies.
“The problem is that probiotics differ from one product to another, both in terms of the organisms and in terms of concentration,” says Professor Worwell.
Emma tried other treatments to avoid a UTI, such as cranberry juice, but the UTIs recurred and she had no choice but to continue taking the antibiotics.
“They helped clear my infection, but they definitely made me gain weight over the years,” she says.
Watch around the clock
How to harness the power of your body clock. This week: turn off your phone 30 minutes before bed
We are often told that the “blue” light emitted by screens keeps us awake if used in the evening, because this wavelength of light disrupts our body clocks.
But while blue light affects the light receptors in the eye that are key to regulating the body clock, the effect on sleep should be small, says Russell Foster, professor of everyday neuroscience at Oxford University.
A 2014 Harvard study that compared how long people took to fall asleep after reading an e-book or a print book, found the difference was only 10 minutes longer after using the e-book, which is “biologically meaningless,” says Professor Foster.
However, using phones, computers, and other screens late at night keeps the brain mentally active — which may prevent us from getting carried away.
To give the mind time to relax, Professor Foster advises turning off all electronic devices, including televisions and smartphones, 30 minutes before bed.